After 22 years at Duke, the Bernhardt Lab is moving to Cornell University in Fall 2026 — read the announcement

We study how ecosystems hold onto and lose carbon, nitrogen, phosphorus, and other essential elements.

The Bernhardt Lab works across forests, floodplains, wetlands, and streams to understand elemental cycling, and how human activity is changing it.

What we ask

Two questions drive everything we do

01

How do ecosystems retain and transform elements and energy?

02

How is the answer to Q1 changing as a result of human activities?

How we think about it

Four connected threads

From the lab's research statement — full text on the Research page.

01

Biogeochemical Regimes of the Anthropocene

Our species has become extraordinarily good at liberating, fixing, transporting, concentrating, and redistributing elements. Modern economies depend on moving nutrients, metals, and synthetic compounds through the environment at enormous rates. The diversity of synthetic chemicals now present in soils, rivers, and sediments has increased rapidly over the past century, and in many places these compounds are interacting with ecosystems in ways we still poorly understand.

02

Ecosystem Control Points in Space and Time

Biogeochemical activity in ecosystems is rarely evenly distributed across space or time. Instead, many processes occur at especially high rates within small features or brief windows in time. These locations and moments — often referred to as ecosystem control points — can have disproportionate influence on ecosystem function.

03

Energetic and Stoichiometric Constraints on Ecosystem Function

Another long-standing theme of our work is the tight coupling between carbon (~energy) and nutrient cycles. Many of the most interesting questions in ecosystem biogeochemistry arise when we consider multiple elements simultaneously rather than treating carbon, nitrogen, or phosphorus in isolation.

04

Disturbance as a Longitudinal and Long-Term Phenomenon

The influence of any landscape patch on downstream ecosystems depends strongly on its position within the watershed and its hydrologic connectivity with other patches. Disturbances that alter the supply or form of biologically important elements, therefore, tend to propagate along hydrologic flow paths.

A welcoming, productive group

Twenty years, one lab, nearly seventy scientists

Since 2004, nearly 70 students, postdocs, and research technicians have come through the lab. Most have gone on to lead their own labs, agencies, and research programs — several of whom co-authored the tribute this quote is drawn from.

"We take our science seriously, we take ourselves… less so."

— caption on a set of lab photos spanning two decades, in Helton, Morse, Sudduth, Ardón, et al., Journal of Hydrology (2023)
Atlantic Beach writing retreat, 2026
Lab reunion at SFS, Spokane, 2026
A pandemic-era outing to New Hope Creek
Exploring the Mud Creek cypress swamp during COVID
Duke River Center reunion bowling party at SFS
An escape room adventure, freshly vaccinated
Goodbye party for Ben Colman
Lakeshore cleanup, 2023
Breakfast at Polly's Pancake Parlor
Lunch in Hubbard Brook's W3 stream
At work in New Hope Creek
Lab curling party, 2025
Goodbye party for Nick Marzolf
Lab Olympics team, 2024
Floodplain adventures at Nyack
Outreach on coastal change with NC high school science teachers
Goodbye party for RavenBier
River Center's "Conifers" lip synch team at SFS
Spencer, Mike, Audrey, and Emily at AGU in San Francisco
StreamPULSE team meetup in Salt Lake City
Team Macrogas in Duke Forest
Timberlake setup crew, February 2007